碳纳米管修饰电极上沙丁胺醇电催化氧化研究

Study on Electrocatalytic Oxidation of Salbutamol at Carbon Nanotubes Modified Electrode

将多壁碳纳米管（MWNT）分散在疏水性表面活性剂双十六烷基磷酸（DHP）溶液中形成稳定、均相的分散液，然后制备多壁碳纳米管-DHP复合膜修饰玻碳电极（MWNT·DHP／GCE）．应用方波伏安法研究了沙丁胺醇在修饰电极上的电化学行为，结果表明，碳纳米管复合膜修饰电极对沙丁胺醇的氧化有良好的电催化活性，其氧化反应为-电子-质子过程，氧化电位比裸玻碳电极负移40mV，峰电流增加了4．5倍．在最佳测试条件下，氧化峰电流与沙丁胺醇浓度在8．3×10^-7～3．3×10^-6mol／L范围内呈良好线性关系，开路富集2min，检出限达1．8×10^-7mol／L．该修饰电极具有良好的重现性、稳定性．

The multi-wall carbon nanotubes （MWNT） were dispersed successfully into water in the presence of dihexadecyl hydrogen phosphate （DHP） and a stable well-distributed suspension. A was formed sensor based on the multi-carbon nanotubes film coated glassy carbon electrode was developed. The electrochemical response of salbutamol was studied by square wave vohammetry. The oxidation peak potential of salbutamol at the modified electrode was observed at 0. 604 V, which shifted about 40 mV negatively. The peak current increased 4.5 folds, in contrast to that at a bare electrode. Under optimal measurement conditions, there was a good linear relationship between the peak current （Ipa） and salbutamol concentration （C） in the range from 8.3 × 10^ -7 - 3.3 × 10^-6 mol/L, and a detection limit of 1.8 × 10^-7 mol/L （S/N =3） was achieved after 2 min of open-circuit accumulation. The performance of this sensor was excelled in the reproducibility and stability. The electro - oxidation of salbutamol was a one-electron and one-proton irreversible process, and the probable electrode reaction was proposed.